Feeding device for drilling machine spindles



April 1, 1930. 'F. c. SPENCER 1,752,465

FEEDING DEVICE FOR DRILLING MACHINE SPINDLES Filed June 27, 1925 2 Sheets-Sheet 1 WW5) I fizz/z/fdjoencer April 1, 1930. F. c. SPENCER FEEDING DEVICE FOR DRILLING MACHINE SPINDLES Filed June 27, 1925 2 Sheets-Sheet 2 Patented Apr. 1, 1930 UNITED STATES PATENT OFFICE V FRANK CALVIN SPENCER, 01 OAK PARK, ILLINOIS, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, 015 NEW YORK, N. Y., A CORIORA'IION OF NEW YORK FEEDING DEVICE FOR DRILLING MACHINE SPINDLES Application filed June 27, 1925. Serial No. 39,900.

This invention relates to feeding devices, and more particularly to power operated fielgding devices for machine presses and the The object of this invention is to provide an attachment for power-fed drill presses, such that the length of the vertical movement of the drill may be predetermined and the mechanism actuated at will.

In accordance with one embodiment of the present invention a foot treadle causes the operating members of a clutch to engage, thereby rotating a cam which is effective for causing the operation of a drill spindle during which operation energy is stored in a spring member serving at the completion of the drilling operation to retract the drilland disengage the clutch members.

Other features and advantages of the invention will become more apparent from the following detailed description and the accompanying drawings, in which Fig. 1 is a perspective view of the inventionshown applied to a drill press, parts being broken away to illustrate certain details more clearly;

Fig. 2 is an enlarged end view of the invention with a dotted view of the cams in another position imposed thereon;

F i 3 is a vertical sectional view taken on the line 33 of Fig. 2, looking in the direction of the arrows, and

Fig. 4 is an enlarged vertical sectional detail view taken on the line 4-4 of Fig. 3, looking in the direction of the arrows.

Referring to the drawings in which like reference characters designate like parts throughout the several views, the numeral 10 denotes the main frame of a drilling machine. An arm 11 adjustably mounted on the frame 10 supports a drill s indle quill 12. A rack 13 cut in one face 0 the quill 12 is engageable by an interior pinion gear keyed to a shaft 14 mounted in the arm 11. An external pinion gear 16 is also keyed to the shaft 14 and a rotation of said gear 16 will rotate the shaft 14 and the interior pinion gear engaging the rack 13, thereby raising or lowering the drill spindle quill 12, dependent upon the direction in which the gear 16 is rotated. Thus the distance a drill 17 is fed into the work and the speed at which it is fed depends on the rotation of the gear 16.

A horizontally disposed rack 19 engages the plnlon gear 16, said rack being held in engagement with the pinion 16 by a guide member 20 mounted on the shaft 14and held 1n position by a nut 21. A groove 22 in said member 20 serves to guide the rack 19. The other end of the rack 19 is adjustably supported in a slot 23 of a pivotally mounted arm 24 by means of a bolt 25, the head of which rides in the slot 23 and is threaded on the end to receive a butterfly nut 26. The arm 24 rotates on a pin 27 which is mounted on the frame 10. Thus the reciprocating motion of the arm 24 moves the rack 19 raising or lowering the drill 17. By changing the position of the rack 19 in the slot 23, the length and the rate of movement of'throw of the rack may be varied and the distance the drill is fed and the rate of speed of the drill regulated.

Means to reciprocate the arm 24 is provided in a clutch mechanism designated in general by the numeral 30. A shaft 31 is mounted in any suitable manner and constantly driven in the direction indicated by the arrow in Fig. 1 by a suitable source of power (not shown). The clutch mechanism (Fig. 3) may be of any suitable type, the cone type being illustrated in the drawings wherein a member 32 is keyed to the shaft 31 by means of a pin 33, as shown in Figs. 1 and 3 and rotates with the shaft. Another member 35 is keyed to a sleeve 36 (Fig. 3) which is rotatably mounted on the shaft 31, said cone member 35 being adapted to frictionally engage the member 32 to transmit the motion 'of the shaft 31 to all mechanism that is mounted on the sleeve 36. A cam 39 is mounted on the member 35 by screws 40, said cam being in engagement with a roller 41 which is rotatably mounted on a shaft 42 held in a projecting portion at the upper end of the arm 24. A tension spring 60 fastened to the frame 10 and rack 19 serves to pull the rack 19 and arm 24 towards the cam 39 to cause the roller 41 to follow the surface of the cam. Fastened to the sleeve 36 by means of an ad justable set screw 43 is a cam 44 with a groove 45 cut therein which forms the surface of the cam as shown in Fig. 1. The periods of engagement of the clutch members may be varied and predetermined by this adjustable feature as hereinafter described. A bell crank lever 46 is rotatably mounted intermediate its ends on the frame 10 by means of a pin 17 and one end of the said lever 46 is fastened to a rod 48, the lower end of which is suitably secured to a foot treadle d9, as shown in Fig. 1. A roller 57 is mounted at the upper end of the hell 0 ank lever 46 by means 0 a reciprocating pin 50 and a compression spring 51 so that a fiat surface 62 of the roller 57 is constantly pressed against the bottom of the groove 45 and the roller normally rests in this position. A chain 52 or similar device is fastened to the sleeve member 36 by means of a pin 53 and is adapted to be wound about the sleeve in a slot 5* formed therein, the lower end of the chain being fastened to a tension spring 55 which is secured to the foot treadle 49.

To operate the mechanism and feed the drill 17 into the work the clutch mechanism must be actuated. The foot treadle 49 is de pressed rotating the bell crank lever lt") through its connection with the foot treadle 49 by the rod 18. This causes the periphery of the roller 57 to exert pressure against the wall of the slot 45 in the cam let. This pressure slides the sleeve 36 and the cone member keyed thereto on the shaft 31 towards the rotating member until it is in frictional engagement with said power driven memher. As hereinbefore stated this engagement of the two operating members of the clutch 30 will transmit the motion of the shaft 31 to the sleeve 56 and all attached mechanism will rotate therewith. The cam 39 will rotate and the roller 41 in engagement therewith will following the surface of the cam, which is cutso that the arm 24 will be rotated, as shown in the dotted lines in Fig. 2. This will move the rack 19 forward and feed the drill 17 into the work. As the clutch mechanism 30 operates, the roller 57 will ride in the slot 15 cut in the cam 44. The fiat surface 62 of the roller 57 rides on a bottom surface of the slot 45 rmtil the cam is rotated far enough for a surface 61 of the cam to compress the spring 51 and eject the roller 57 from the slot This will release the pressure exerted against the wall of the slot 45 and allow the cone member 35 to be forced out of engagement with the member 32 by means of spring pressed plungers 66 shown in Fig. 3.

The chain 52 will be wound around the sleeve 36 in the groove 5% while the mechanism is rotating, creating a tension on the spring 55. When the clutch mechanism 30 has been released by the cam 44 the energy stored up in the spring 55 while the chain 52 was wound around the sleeve 36 will serve to rotate the sleeve and return the associated mechanism back to the starting position. Thus, the cam 39 will be rotated in the opposite direct-ion and the roller 41 will follow the surface of the cam re" irning the arm 2% and the rack 19 to its start "1g position, thereby extracting the drill 1? from the work. In this manner the clutch mechanism 30 serves to automatically retract the drill after it has been fed a predetermined distance into the work.

It will readily be seen that the distance which the drill 17 will be fed depends on the distance that the cam 4-4. is to rotate before the surface 61 thereof engages the surface 62 of the roller 57 and ejects the roller from the slot 45. Thus by changing the position of the cam i l said distance may be varied.

The mechanism herein described is operated by a foot trcadle leaving the operators hands free to handle the work. The depths of the holes to be drilled can be predetermined and the drill will be retracted from the work automatically at the completion of the operation or during an operation at the will of the operator, the drill being under complete control of the operator at all times. It is to be understood that while the invention is shown applied to a single spindle drill press it is adaptable for a plurality of spindles and its scope limited only by the appended claims.

What is claimed is:

1. The combination with a drill press including a drill spindle, of means for imparting vertical movement to the spindle comprising a clutch mechanism including driving and driven members, one of said members having an external slot therein, resilient means for maintaining the driving and driven members normally separated, manual means for engaging said members, a cam associated with and operated by the clutch mechanism, a rack reciprocated by the cam to impart a longitudinal motion to the drill spindle, means to disconnect the manual means after the drill spindle, has been moved a predetermined distance, means to adjust said last mentioned'means to vary the predetermined dis tance, a member wound in the slot by the rotation of the clutch mechanism and a spring attached to the last mentioned member for storing energy during the winding operation to co-operate with the resilient means for re turning the clutch members and all associated mechanism to their starting position upon the operation of the disconnecting means.

2. The combination with a drill press in.- cluding a drill spindle, of means for imparting vertical movement to the spindle comprising a driving member and a driven member, resilient means for maintaining the driving and driven members, normally separated and manually operated means for operatively engaging the driving and driven members, a

its

cam associated with and driven by the driven member to transmit a vertical motion to the drill spindle When the members are engaged, means carried by one of the members to disconnect the members upon the travel of the drill spindle for a predetermined distance, means for adjusting the last mentioned means to change its eifectiveness to provide for the travel of the drill spindle for a different distance, and a member Wound about the driven member by its rotation during the engagement thereof With the driving member to store energy and rendered effective upon the disconnection of the driving and driven members to co-operate With the resilient means for returning the driven members to its started position.

In Witness whereof, I hereunto subscribe my name this 18th day of June, A. D. 1925.

FRAN K CALVIN SPENCER. 

